Field of the Invention
The invention lies in the printing field. More particularly, the invention relates to a method and a device for force loading a rubber roller in the inker and dampener of a printing press.
Rubber blanket rollers are used in inkers for ink transfer from the take-up roller to the impression cylinder and in dampeners for the transfer of dampening solution from one cylinder to another. The rubber roller must thereby be biased, i.e. force-loaded against the other rollers. In the printing-off position of the printing unit or for cleaning the blanket it is advantageous to throw the blanket roller off the other rollers. In production use, furthermore, the rubber covering may swell with increased heat and due to other dynamic effects and the loading pressure of the rubber blanket on the counter-rollers thus changes during operation.
Many prior art systems do not allow for a dynamic adjustment during a production run. The rubber rollers are thereby force-loaded by adjusting the respective inker and dampener position setting sockets during the production setup. This leads to a difficult and time consuming setup procedure. Also, the set adjustment does not allow compensation for temperature and roller swelling.
One system has been proposed wherein the rubber rollers are adjusted by way of motors. The system with the motorized adjustment of the rubber rollers is complicated and requires a high degree of maintenance. Furthermore print quality suffers with the inadequate compensation of temperature effects.